[Freeswitch-dev] The gentones application generates a very bad quality sound

Anton freeneutron at gmail.com
Sun Nov 17 06:46:10 MSK 2013

I try to transfer the sound of 1,000 Hz from FreeSwitch to the browser and 
watch the quality of the sound, depending on the client type. Especially 
for this experiment, I created an external sip-profile:
    <gateway name="sip2sip.info">
        <param name="username" value="soundtest"/>
        . . .

     and following dialplan:
        <extension name="soundtest at sip2sip.info">
            <condition field="destination_number" expression="^soundtest$">
                <action application="gentones" data="%(3500,0,1000)|-1"/>

        <extension name="mod_rtmp">
            <condition field="source" expression="^mod_rtmp$">
                <action application="gentones" data="%(3500,0,1000)|-1"/>

And reproducing clients:
http://call2sip.ru - created on the basis of SIPml-api (correct work only 
under the Chrom)
and http://soundtest.iiiii.info - created on the basis of mod_rtmp flex-
client side

Sound is produced as a result of the test recorded on the mic.

At first, made ​​the call from the SIPml-client to the number 
soundtest at sip2sip.info and recorded the resulting sound. Then made ​​a call 
from the flex-client (in which case the destination number does not matter) 
and also recorded the resulting sound. Both sound recorded in a single 
file. Here's a link to this file:

As you can see this, copies of the same signal are quite different in 
quality. In other words, the sound reproduced through the flex contains a 
very noticeable defects.
But it is only in the case where the sound is played in Windows 7. About 
other systems say anything until I can not. In this Friswitch was running 
on a remote server on CentOS 6.3. 
Yet I performed the same test when Friswitch was launched in the same 
system that plays sound. In this case, 50% of attempts were given a faulty 
sound, and the remaining 50% were given a normal tone.
I also tried to listen to the audio tone through this service:
And he also got a lot of noise.

I would like to know whether it is possible to somehow get rid of this 
noise? Not giving up the use of flex-technology.

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